Found on top of a mountain in South Africa Gauteng province. Magnetic and is 3 times heavier than expected

[u/RepresentativeFar92]

[u/PicrolitePicker]

It looks very much like ferrous slag.

[u/JimmehROTMG → u/PicrolitePicker]

seconding slag (not volcanic)

[u/Joe_df]

This looks like slag to me...

[u/Debtcollector1408]

Iron rich slag, I'd bet. How it got there is a question of history, not nature.

[u/jessybiteslip]

That looks exactly like industrial slag from local mining operations, which is incredibly common in Gauteng. It is dense and magnetic because of the iron content, but definitely not a meteorite.

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[u/RepresentativeFar92]

Thank you for sharing

[u/RepresentativeFar92 → u/RepresentativeFar92]

It is not metal because if you use a big hammer with two hands it can break a little piece

[u/robo-dragon → u/RepresentativeFar92]

Metal slag can be brittle. Unless it’s been through some kind of hardening process, iron can break pretty easily.

[u/mc68n → u/robo-dragon]

I smashed a whole cast-iron stove to pieces with a sledgehammer back in the day.

[u/bigselfer → u/mc68n]

Brittle iron vs ductile sledge. I bet that was fun.

[u/SneakySquiggles → u/RepresentativeFar92]

Yes because metal is.. totally unbreakable

[u/ConfIit → u/RepresentativeFar92]

Slag is often very brittle as it contains a lot of impurities

[u/winxminx9 → u/RepresentativeFar92]

Im not an expert on normal rocks but metal slag can be very brittle meaning a hammer would easily break pieces off.

[u/Fun_Push7168 → u/RepresentativeFar92]

There are basically no materials you could find in " rock" form that are ferromagnetic and not metal.

[u/Dimizigus → u/RepresentativeFar92]

how tf it’s magnetic then? metal breaks too

[u/Old_Mycologist1066]

It could be a meteorite....It certainly sounds like that..

[u/PicrolitePicker → u/Old_Mycologist1066]

those giant vacuoles are a big strike against a meteorite. A meterorite shouldn't appear metallic unless cut or sanded due to their dark "fusion crusts"

[u/MASSochists → u/Old_Mycologist1066]

Meteorites shouldn't have holes like that.

[u/doc1442 → u/Old_Mycologist1066]

Only if you don’t know the first thing about meteorites, and this sub is practically the “why is this rock not a meteorite” sub.

It’s slag.

[u/Adorable-Bus1697 → u/doc1442]

It's always slag.

[u/MetalPlayer666 → u/Adorable-Bus1697]

Not quite ALWAYS just slag/meteorite on this sub...
You forgot about the "it's not gold, just pyrite." We should make some sort of a bot to count both types of question and see which one pops up more often. 🤣

[u/Ok_Test9729 → u/Adorable-Bus1697]

Or it’s always pokeweed.